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  • This statement gives the results of a scout drilling campaign conducted by the Bureau at the Kirby's Hill Area of the Western Coalfield of New South Wales. The area investigated comprises approximately 200 acres of the parish of Cullen Bullen in the County of Roxburgh. At Kirby's Hill itself a maximum of about 300 feet of Coal Measure rocks rests on Upper Marine beds, and this is one of the most westerly exposures of the Upper Coal measures. The purpose of scout drilling was to determine the suitability of the Lithgow and Irondale Seams for open cut exploitation.

  • Like many of the basins along Australia's eastern seaboard, there is currently only a limited understanding of the geothermal energy potential of the New South Wales extent of the Clarence-Moreton Basin. To date, no study has examined the existing geological information available to produce an estimate of subsurface temperatures throughout the region. Forward modelling of a basin structure using its expected thermal properties is the process generally used in geothermal studies to estimate temperatures at depth in the Earth's crust. This process has been validated for one-dimensional models such as a drill hole, where extensive information can be provided for a specific location. The process has also seen increasing use in more complex three-dimensional (3D) models, including in areas of sparse data. The overall uncertainties of 3D models, including the influence of the broad assumptions required to undertake them, are generally only poorly examined by their authors and sometimes completely ignored. New methods are presented in this study which will allow estimates and uncertainties to be addressed in a quantitative and justifiable way. Specifically, this study applies Monte Carlo Analysis to constrain uncertainties through random sampling of statistically congruent populations. Particular focus has been placed on the uncertainty in assigning thermal conductivity values to complex and spatially extensive geological formations using only limited data. These geological formations will typically consist of a range of lithological compositions, resulting in a range of spatially variable thermal conductivity values. As a case study these new methods are then applied to the New South Wales extent of the Clarence-Moreton Basin. The structure of the basin has been built using Intrepid Geophysics' 3D GeoModeller software package using data from existing petroleum drill holes, surface mapping and information derived from the FrOGTech SEEBASE study. A range of possible lithological compositions was determined for each of the major geological layers through application of compositional data analysis, using data from deep wells only (>2000 m). In turn, a range of possible thermal properties was determined from rock samples held by the New South Wales Department of Primary Industries and analysed at the Geoscience Australia laboratories. These populations of values were then randomly sampled to create 120 different forward models which were computed using SHEMAT. The results of these have been interpreted to present the best estimate of the expected subsurface temperatures of the basin, and their uncertainties, given the current state of knowledge. These results suggest that the Clarence-Moreton Basin has a moderate geothermal energy potential within an economic drilling depth. The results also show a significant degree of variability between the different thermal modelling runs, which is likely due to the limited data available for the region.

  • During an inspection of limestone deposits at White Rocks on 2/11/50, samples of weathered granite were collected from a quarry on the eastern side of the Queanbeyan-Cooma road, about 150 yards south of the two-mile peg. This quarry is in the Queanbeyan Clay Deposit described by W.G. Woolnough in departmental reports dated 17/2/28 and 20/6/28. If the rock can be economically crushed and worked, it may be suitable for the production of sewer-pipes and other impervious ware. The samples, reserves, and suitable uses for the granite are described in this report.

  • A reconnaissance geological and radiometric survey of the Mt. Cavenagh area was carried out by B.P. Walpole and J. Sleis of the geological section and J. Daly and D. Dyson of the geophysical section of the Bureau of Mineral Resources. The objects of the survey were to examine reported occurrences of radioactive minerals in this area and to determine whether further prospecting of the area for radioactive orebodies was warranted. The general geology of the area, and the economic geology of the six prospects examined, are described in this report.

  • Rock properties provide the vital link between observed geophysical data and interpreted geology. Geoscience Australia has periodically made measurements of rock properties to support various investigations into the composition and structure of the subsurface. The Rock Properties Project consolidates this information into a single database structure and makes it accessible to external clients via a web delivery application. We have chosen to initially concentrate on mass density and magnetic properties, as these are of prime importance to the important gravity and magnetic datasets maintained for the Australian region by Geoscience Australia. Additional property types and more extensive datasets will be added over time.

  • The information presented in this paper was collected in 1947-8 by a combined scientific team composed of officers from the Commonwealth Scientific and Industrial Research Organization and the Commonwealth Bureau of Mineral Resources, Geology and Geophysics, who carried out a reconnaissance of the natural resources of the Barkly Region. The subsurface water supplies and the geological features which assist in determining the characteristics of water supplies are discussed in this report.

  • Six wax-sealed samples of cores were received with a request that they be tested for porosity, permeability and oil and water content. Testing was carried out by Messrs. N.V.H. Hoyling and H.S. Taylor-Rogers at the Newcastle Technical College - to the Principal and Staff of which institution grateful acknowledgment of their co-operation and utilization of their apparatus and laboratory space is made.

  • In connection with the search for uranium in Australia samples of mill products from producing mines have been examined for radioactivity by the Bureau. Amongst these were several samples from mines at Broken Hill. A preliminary examination showed that the uranium content of the samples was certainly much less than 0.01 per cent. To obtain more accurate data, the samples were re-examined by more sensitive methods, and the results of these are tabulated below.

  • A deposit of weathered graphic granite at White Rocks, 2 miles south of Queanbeyan, was investigated and the limits of material in it suitable for easily quarryable road metal were determined. The area was divided into two sections: a northern one held for the most part by the Queanbeyan Council, and a southern section at present held privately as a grazing lease. "Indicated" reserves, based on the present quarrying level, of 170,000 cub. yds were established in the northern section. Most of this material will be of the same quality as that being quarried at present; some of the material towards the southern boundary of the lease will however be harder and require more blasting. In the grazing leases "inferred reserves" of 140,000 cub. yds. were delineated. It is expected that this material will be quite suitable for road making but may be slightly inferior in sizing to the material at present being quarried; also it may require more blasting in some portions than the material being quarried at present; it will carry a higher average overburden than the Queanbeyan lease.

  • Bearing in mind Mr. Kitchin's statement that the mica has been recovered from a shallow depth of about six feet only it appears to be of really good quality, and in view of the shortage of clearer types of mica it seems desirable that the deposit should be examined. The four mica specimens submitted for examination are described herein.